What are the basic steps of how a bill becomes a law?

The bill is first introduced to Congress by either a senator or the person who is sponsering it. If it is approved by voting, it goes to the president who can approve or veto it. In most cases, however, if Congress still takes a liking to it, they can override the bill and it will still become a law.

i believe the correct answer is option b. most eastern european nations joined nato.

though i could be wrong, option d. the eastern european nations were granted complete independence, would be another choice.

hope this ! : )